Veins can become incompetent through the weakening of blood vessel walls or damage to or weakening of valves within the vein. Most frequently, veins carrying oxygen-depleted blood up the legs provide the most apparent visual evidence of the vessel wall or valve weakening, demonstrating that a portion of the veins have become incompetent. When the blood vessel walls weekend or the valves no longer serve their function of reducing or preventing backflow of blood, the vain can become enlarged, weak, and twisted. This condition is referred to as a varicose vein.
While the causes of varicose veins are varied and common, varicose veins can be treated using a variety of procedures.